The invention described herein may be manufactured and used by the U.S. Government for governmental purposes without the payment of any royalty thereon.
1. Field of the Invention
The invention relates to disposable packages and methods for making same, and is directed more particularly to a method for making a package for a substance activatable by an activating agent, typically water, and the package made thereby.
2. Description of the Prior Art
Disposable packages for water activatable substances are generally known. A number of such packages are referred to as xe2x80x9cflameless heatersxe2x80x9d and are provided with substances which, upon contact with water, produce heat, for warming the hands of a person, or for warming a food tray, or the like. Examples of such devices may be found in U.S. Pat. No. 5,390,659, issued Feb. 21, 1995, U.S. Pat. No. 4,522,190, issued Jun. 11, 1985, U.S. Pat. No. 5,517,981, issued May 21, 1996, U.S. Pat. No. 5,935,486, issued Aug. 10, 1999, and U.S. Pat. No. 5,611,329, issued Mar. 18, 1997. Inasmuch as such packages are used only once and disposed of, there is needed a package which is very inexpensively produced, easily used, and adds function to the activatable substance.
In some packages the activating agent and the exothermic heating agent are both packaged, but segregated from each other by a barrier, with a means to break the barrier to allow the active agent to mix with the heating agent. Such packages are necessarily relatively complex and expensive to make.
In other packages, the activating agent, usually water, is added to the package from an outside source. The ""659 patent is of the latter sort and includes structure for receiving and metering water. The additional structure adds costs to the manufacture of the package and results in an awkward configuration of package.
Still other packages require a tool or implement to open or alter the package to introduce water or other activating agent to the heat generating agent.
Accordingly, there is a need for a very simple package which is inexpensive to manufacture, easy to use without any implements, and which indicates very inexpensively how much activating agent to add to the activatable substance, such as an exothermic chemical heater, and which adds function to the activatable substance.
There is further a need for a functional disposable package for sealingly retaining and preserving an activatable substance and for providing means by which an activating agent can be added to the substance in the package. For moisture sensitive substances, a high-moisture-barrier package is needed. Such packages require the use of opaque high-barrier materials which are hermetically sealed to provide extended shelf-life characteristics.
There is similarly needed a method by which this integrated functional package can be easily and inexpensively made.
An object of the invention is accordingly to provide an inexpensive, easy to use, disposable package for sealingly retaining an agent activatable substance, such as an exothermic chemical heater, the agent being, for example, water, and having facility for admitting a measured amount of agent into the same package to contact the substance at the time of use. A principal feature of the invention is the dual-purpose utility of the package that eliminates the need for an additional package or secondary materials that serve both the storage requirements for a high-barrier package and the operational requirements for measuring and delivering an actuating agent to the package upon use. A principal benefit of the invention is the reduced size, weight, and ease of use characteristics provided by the integrated functional configuration.
A further object of the invention is to provide a method for making such a package.
With the above and other objects in view, a feature of the present invention is the provision of a method for making a disposable package for an agent activatable substance. The method comprises the steps of providing a substantially planar support member of a moisture and air barrier material, mounting on a major surface of the support member a sheet at least in part translucent, the sheet being mounted within all boundaries of the support member surface, sealing all but one edge of the sheet to the support member to provide a pocket fixed to the support member, placing the agent activatable substance in the pocket so as to occupy only a portion of the pocket, folding the support member and pocket upon themselves, and releasably sealing overlying portions of the support member together along all but a folded edge of the support member to enclose the agent activatable substance. There is thereby provided a method for making a hermetically sealed package which is openable by separating the overlying portions to expose the pocket for introduction of an agent into the pocket to activate the agent activatable substance therein.
In accordance with a further feature of the invention, there is provided a disposable package for an agent activatable substance. The package comprises a substantially planar support member of a moisture and air barrier material, a pocket of material, at least in part translucent, mounted on the support member, the pocket being open along one side thereof, an agent activatable substance disposed in the pocket and occupying only a portion of the pocket, the support member and the pocket being folded upon themselves, the support member being releasably sealed along all overlying edge portions other than a folded edge. There is thus provided a package which is readily openable without the use of a cutting implement by separating the overlying releasably sealed edge portions to expose the pocket open side for introduction of an agent into the pocket for activating the agent activatable substance, and thereby not compromising the integrity of the pocket.
The above and other features of the invention, including various novel details of construction, function and combinations of method steps and parts, will now be more particularly described with reference to the accompanying drawings and pointed out in the claims. It will be understood that the particular method and device embodying the invention are shown by way of illustration only and not as limitations of the invention. The principles and features of this invention may be employed in various and numerous embodiments without departing from the scope of the invention.